Balanced steam-turbine.



PATENTBD DOT. 23; 1966.

-- I w. L. WEBSTER.

BALANCED STEAM TURBINE. APPLIOAT IOH F I LED NOV. 17. 1903. RENEWED-JUN 29, 1906.

PI G. 2.

' UNITED STATES i PATENT WILLIAM,- LLOYD Specification of Letters Patent. Application and November 17, 1903. Renewed m. a. 1900. Burial m.

Patented on. as, ieee.

.To all whom it may concern:-

'Be it known that I, WILLIAM LLOYD Wns-' s'rnn, a citizen of the United States, residin at New York, in the county of N ew Yorkan Steam-Turbines, specificationp shaft and working State of New York, have invented certain new and useful Improvements in Balanced of whichthe following is a.

This invention relates to a thrust-balance for steam-turbines.

The object of the invention is to produce a stean1-turbine in which the end thrust is wholly or partially overcome by the pressure or disks connected to the of steam on a disk in a balance chamber or chambers, itS Wlll e described' The 'inventlon conslsts 1n comblnations and constructions of mechanical elements whereby steam-pressure 1n the balance cham-' ber or chambers will bear with an excess of pressure on-the balancedisk or disks to that which bears on the rotary iston" or motor part of the engine, as will e explained and clalmed.

The drawings illustrate only one of. numerare explanator not working, drawings.

- igure lis a longitudinal section of a turbine embodying my invention. Fig. 2 is a the piston I a cross-section on line aim, Fig.1, adisk 7 being partly broken away. i

Let the numeral 1 illustrate the casingof a iston or motor part of the engine, and 3 the s aft. All these parts may be of any usual form or construction. The steam after passing the inlet end 10 of the working chambers operates as usual on the blades ofth'e rotating piston and fixed chamber.

At the inlet end of the engine there are formed integral or rigid withthe casing as many balance-chambers 4 4 as may be desirable. At the side toward the piston there is afxed partition 5 5 in each chamber,

through which. partition the shaft 3 passes with as close a fit as can easily be made without much friction.

At the side of each chamber 4 remote from ttach to the shaft 3 a disk 7, urrounded by a fixed annular wall 8, refera 157 forming part of the casing. Throug the wall 8 a by-passage or a number of passa es 9 extend to the inlet end 10 of the piston-c amber of the engine.

which disk is area 0 equalized on bothfaces of Steam-pi ea 11 convey the full boiler-pressure, 'or sue -steamressure as may be' employed, to each cham 'er 4. The walls 5 prevent direct'entrance ton-chamber; around. the periphery of the disks? to thebyggssages 9 throu h which passages the steam ds its way to c amber 10, and so throu h the engine, as usual, exhausting at 12.- T e the passage around disk 7 and between it and wall 8 is less than the area of inlet-pipe T1. Oonsequentl the steam passin out of chamber 4 aroun disk 7 Y is throttled own or reduced in pressure afterpassing. The passage between disk' 7 and wall 8 is narrow, so that full pressure in the chamber sis not allowed to escape in this way to the by-pas sages 9.; An excessof pressure then becomes exerte on the face of disk 5, which is -within chamber 4. Thus suppose boilerpressure. at one hundred ounds per square inch be admitted to charm er 4 an only seventy-five pounds can escape. through the annular passage around disk 5, then the excess of ressure of twenty-five ounds per square inch will tend to thrust isk 5 and shaft 3 away from the piston 2 or, in other words,

will balance the pressure .on the piston and disks to that extent. In such case a series of three or four balance-chambers and disks would by the excess of pressure'bearin away from the piston practically overcome t e end thrust of'the piston and connections.

In the drawings Ihave shown an excess of ,t'he space likely to exist between the disks 5 and the Walls '8, as a very narrow opening around a large disk will pass a great amount of steam; but the theory of operation will be understood from the-description and illus tration.

For convenience of o eration and to be able 'to dis )ense with t e balance-pressure when full )oiler-pressure is desired on the piston or to be enabled to adjust the excess of pressure without changing disks 7 I provide an opening 14 from each chamber 4 and a valve 15, by which this opening may be closed or left partly open. 15 the steam from chamber 4 is admitted to the by-passage 9 and thence passes directly to the piston-chamber:- The throttlin of the steam and balancing efiectof the discs 7. is thus diminished insofar as the pressure is the disks 7. Of

OFFICEQ WEBSTER, or new YORK, N. Y. l BALANCED STEA -rename.

of the steam to the pis- I The steam must then escape,

too

By opening valve course a singledisk 7 could be made so large that an excess of'pressure againstone side would balance the piston thrust; but with large engines this would be an unwieldy construction.

The small amount of leaks e of steam through the passages around s aft 3 where it passes through walls 5 would act as a lubricant, and the steam thus entering istonchamber 10 would work effectively in riving the piston.

I. am aware that many attempts have been made to balance or overcome t e end thrust of the shaft in steam-turbines by constructing the engine with double pistons and casings having steam entrance at the middle and exhaust at each end or by having a steam-supply at both ends and exhaust at the middle. An objection to either plan is that the iston is thereby made much longer in axialow engines, that the expense of construction is practically doubled, and that there is difficulty in. fitting. The space occupied by balance-disks on my plan may be very small, and the disks, being exposed to smkall differential pressure, may be thin and i to l lt has been common to attach a balance to the shaft of a rotary engine, said disk. fitting closely'to the end of the casing and intended to have a tight joint therewith. This causes much friction about the periphery of the disk. What steam does leak past the disk is carried to the exhaust and absolutely lost. The shaft of my engine may be mounted in the casin in any usual form of stuliing-boxes. The c osed bearing at the balanced end of the engine may be lubricated in any desirable manner. The casing can be cast in sections,

to 'be joined to ether as usual, thus permitting access to all the parts. No special now elty is claimed for the casing, except that the balance-chambers are made rigid therewith, and steam is normally admitted to the pistonchamber after throttling down in the balance chamber or chambers to secure the excess of pressure for the purpose of balancing end thrust.

What I claim is 1. In a steam-turbine, the combination with the shaft of a balance-disk attached thereto, a chamber surrounding the disk, and steam inlet and outlet passages from said chamber arranged so as to give an excess of steam-pressure on one face of the disk and an escape-passage from the balance-chamber leading to the working chamber of the engine.

2. In a steam-turbine, the combination witha piston, a shaft, and a casing, of a alurality of balance-chambers, a balance-dish in each chamber connected to the shaft, and steam-passages leading from the balancechambersto the working chamber of the engine whereby an excess of steam-pressure is normally applied to the faces of the disks which thrust in opposition to the piston.

3. The combination with a casing, piston, and shaft for a steannturbine, of a balancechamber, a disk on the shaft within said chamber, and a controllable by-passagc leading from. the balancechambcr to the pistonchamber.

4. The combination with a piston, shaft and casing for a steam-turbine, of a balance chamber with wall. rigid with the casing, a

balance-disk on the shaft and having one face in said chamber, a bypassagc leading from one side of the baiaiuze-disk to the piston-chamber, and a by-passago having a con-- trollirw-valve leading from the other side of the dis lr to the piston-chamber.

5. In a steam-turbine, a casing having a longitudinal shaft therein, a piston on said shaft having usual blades thereon and blades within the casing cooperating with the pistonblades, a balance-chamber having walls rigid with the casing, and a l'ialance-disk within said chamber, a steam-supply pipe leading to said chamber, an exit-passage around said disk of less area than the sup ily-pipe, and a passage leading the steam which passes the disk to the piston-chamber.

6. In a steam-turbinc the combination of a casing containing a rotating piston and shaft of usual construction, of a balance-disk secured to said shaft and rotating in a separate chamber in the casing, a live-steam passage leading to the balance-chambcr on the side of the balance-disk calculated to relieve the end thrust of the piston, and an exhaust- )assage leading from the opposite side of the balance-disk to the working chamber of the engine.

ln testimony whereof I allix my signature in presence of two witnesses.

, WILLIAM LLOYD WEBSTER.

Vi itnesses: v

John D. Bnownn, Flinn J. STARR. 

